How to access array element sequentially in for loop?

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Hello,
I have 5 dataset:
data1=rand(1,1000)
data2=rand(1,1000)
data3=rand(1,1000)
data4=rand(1,1000)
data5=rand(1,1000)
To run my simulation, I am running a for loops for i=1:200 (running for loops for 200 times) where when i=1, I have to select the 3 data from data1 starting from index 1 to 3, then from data2 I have to select 2 data and similar way way from all the arrays.
I have to select the values sequentially and a non-repetitive way. That means, when i=2, I have to select data from data1 from index 4 to 6.
Then I will use that data in for calculation. Like, result would be:
result = data1(index1) + data2(index1);
result2=data1(index2) + data2(index2);
at the end of the simulation, I will have result vaules that contains 200 data.
Thank you so much for your time and considerations.
  3 Comments
Tania Islam
Tania Islam on 4 Jul 2020
Thank you so much for your reply.
Actually I wil use the data1 with others data. I will select data from each dataset.
Tania Islam
Tania Islam on 4 Jul 2020
Edited: Tania Islam on 4 Jul 2020
My whole pocess is for i=1,
Result1(index1)=data1(index1)+data1(2)
Result2(index1)= data2(index1)+data2(index2)
result3(index1)=data1(index3)+data2(index1)+data3(index1)
result4(index1)=data1(index4)+data3(index2)
And i want to continue this process for i=200,where array index should be in sequential way.
like following way:
Result1(index2)=data1(index5)+data1(index6)
Result2(index2)=data2(index3)+data2(index4)
result3(index2)=data1(index7)+data2(index3)+data3(index3)
result4(index2)=data1(index8)+data3(index4)
Thank you for your time and considerations.

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Answers (2)

Steven Lord
Steven Lord on 4 Jul 2020
Rather than creating numbered variables (which is generally discouraged) consider making a matrix or array containing all your data.
data = rand(5, 1000);
q = data(3, 42) % what you would call data3(42) in your original code
I have no idea what pattern you're using to try to extract elements from your data so I can't give any advice about that part. If you describe that pattern in more detail we may be able to help you determine the most efficient way to extract the data.
  5 Comments
Walter Roberson
Walter Roberson on 17 Jul 2020
Tania, you are incrementing i_value by 4 at a time, but you use up to data1(i_value+4) . On the first iteration you would use data1(1), data1(2), data1(4), data1(5) (but not data1(3)) . On the second iteration you would use data1(5), data1(6), data1(8), data1(9) (but not data1(7)) . Is it correct that you want to use data1(5) in the first iteration and also use it in the second iteration?
Is it correct that every iteration you want to use data3(1), as well as some other values of data3 ?

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Raj Kumar Bhagat
Raj Kumar Bhagat on 10 Jul 2020
Edited: Raj Kumar Bhagat on 10 Jul 2020
I have used 2 more variable to keep track of data2 and data3 index.
Running the following loop we will be able to select data from these data vectors. The data are stored in variable from delay1 to delay6
Hope this helps.
if true
data1=rand(1,1000);
data2=rand(1,1000);
data3=rand(1,1000);
len=200;
trigger=2;
count1 =1;
count2 =1;
for i_value= 1:3:len
% selecting 3 data from data1
delay1=data1(i_value);
delay2=data1(i_value+1);
delay3=data1(i_value+2);
% selecting 2 data from data2
delay4=data2(count1)
delay5=data2(count1+1)
count1 = count1+2;
% selecting 2 data from data2
delay6=data3(count2)
count2 = count2+1;
end
% code
end

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